Dendritic cell vaccine containing telomerase reverse transcriptase for the treament of cancer

ABSTRACT

The invention provides a method of activating a T lymphocyte by contacting the T lymphocyte with a dendritic cell (DC) that presents a telomerase reverse transcriptase (TRT) peptide in the context of a MHC class I or MHC class II molecule. The DC may be pulsed with a TRT polypeptide or may comprise a recombinant polynucleotide encoding a TRT such as hTRT. The invention also provides DCs comprising a recombinant TRT polynucleotide. The methods and compositions of the invention are used in prevention and treatment of cancers and other cell proliferation diseases or conditions.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Patent Application PCT/US99/06898, filed Mar. 30, 1999 and designating the U.S., pending; which claims the priority basis of U.S. provisional application 60/112,006, filed Mar. 31, 1998, expired. The PCT application is hereby incorporated herein by reference in its entirety.

Also incorporated herein by reference in their entirety are the following: U.S. applications Ser. No. 08/974,549, U.S. Pat. No. 6,166,178; Ser. No. 08/974,584; Ser. No. 08/915,503, abandoned; Ser. No. 08/912,951; Ser. No. 08/911,312, abandoned; and International Applications PCT/US97/17618 and PCT/US97/17885.

FIELD OF THE INVENTION

The present invention is related to the catalytic protein subunit of human telomerase. The invention provides methods and compositions relating to medicine, immunology, and molecular biology.

BACKGROUND OF THE INVENTION

The following discussion is intended to introduce the field of the present invention to the reader. The citation of references in this section should not be construed as an admission of prior invention.

The telomerase ribonucleoprotein complex is a specialized polymerase that maintains telomeres, the specialized structures at the ends of eukaryotic chromosomes. The length and integrity of telomeres in a cell is correlated with the entry of the cell into a senescent stage (i.e., loss of proliferative capacity), or, alternatively, the ability of a cell to escape senescence. Of particular interest is the correlation observed between telomerase activity in human and other mammalian cells and the development of a neoplastic phenotype. For example, telomerase activity is detected in immortal cell lines and a diverse set of tumor tissues, but is not detected (i.e., was absent or below the assay threshold) in normal somatic cell cultures or normal tissues adjacent to a tumor (see, U.S. Pat. Nos. 5,629,154; 5,489,508; 5,648,215; and 5,639,613; also see, Morin, 1989, Cell 59: 521; Shay and Bacchetti, 1997, Eur. J. Cancer 33:787; Kim et al., 1994, Science 266:201 1; Counter et al., 1992, EMBO J. 11:1921; Counter et al., 1994, Proc. Natl. Acad Sci. U.S.A. 91, 2900; Counter et al., 1994, J. Virol. 68:3410). Moreover, a correlation between the level of telomerase activity in a tumor and the likely clinical outcome of the patient has been reported (e.g., U.S. Pat. No. 5,639,613; Langford et al., 1997, Hum. Pathol. 28:416).

Thus, telomerase plays an important role in the control of cell proliferation and in tumorigenesis. For these and other reasons, human telomerase is an ideal target for preventing and treating human diseases relating to cellular proliferation and senescence, such as cancer. The present invention provides immunological methods for preventing and treating these and other diseases in humans and nonhuman animals.

BRIEF SUMMARY OF THE INVENTION

In one aspect, the present invention provides a method of activating a T lymphocyte by contacting the T lymphocyte with a dendritic cell that expresses a telomerase reverse transcriptase (TRT) polypeptide encoded by a recombinant nucleic acid. In various embodiments of the invention, the TRT polypeptide is a human TRT (hTRT) polypeptide, and may have the sequence set forth in FIG. 1, or may have a subsequence thereof. In one embodiment, the hTRT polypeptide is full-length. In one embodiment, the dendritic cell is a human cell. The dendritic cell may contact the T lymphocyte in vivo or in vitro.

In a related aspect, the invention provides a recombinant dendritic cell which comprises a recombinant TRT expression cassette. In one embodiment, the recombinant expression cassette is transduced into a stem cell, and the stem cell is then differentiated into the dendritic cell. In one embodiment, the stem cell is differentiated in vitro. The invention also provides a pharmaceutical composition comprising the aforementioned dendritic cell and a pharmaceutically acceptable carrier.

In another aspect, the invention provides a method of eliciting an immune response in a human patient by (a) obtaining human dendritic cells, (b) transducing a TRT expression cassette into the cells so that they are capable of expressing a hTRT polypeptide, and (c) administering the cells to the human patient. In certain embodiments, the dendritic cells are isolated from the human patient to which they are administered, and/or are obtained from hematopoietic precursor cells.

In yet another aspect, the invention provides a method of eliciting an immune response in a human patient by (a) obtaining human dendritic cells, (b) pulsing the cells with a hTRT antigen, and (c) administering the cells pulsed with the hTRT antigen to the human patient. In certain embodiments, the dendritic cells are isolated from the human patient to which they are administered, and/or are obtained from hematopoietic precursor cells. In one embodiment the cells are pulsed with one or more hTRT antigenic peptides that are less than 50 amino acid residues in length 122

In another aspect, the invention provides a method for identifying a cell expressing hTRT. According to the method, a dendritic cell is transduced with a recombinant expression cassette comprising a nucleic acid encoding a hTRT polypeptide; a T lymphocyte is contacted with the transduced dendritic cell, thereby providing an activated T lymphocyte; and a target cell is contacted with the activated T lymphocyte. The effect of the activated T lymphocyte on the target cell is then monitored.

DESCRIPTION OF THE FIGURES

FIG. 1 shows the amino acid sequence (in the one-letter code) (SEQ. ID NO:2) of a 1132-residue hTRT protein.

FIG. 2 shows a nucleic acid sequence (SEQ. ID NO:1) of a cDNA encoding the hTRT protein shown in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

I. Definitions

As used herein, “telomerase reverse transcriptase” (TRT) refers to the catalytic protein subunit of the telomerase ribonucleoprotein particle. TRT from humans has been characterized, human TRT (hTRT) genomic and cDNA sequences have been cloned and their sequences determined. See, e.g., Nakamura et al., 1997, Science 277:955 and U.S. patent applications Ser. Nos 08/912,951 and 081974,549, U.S. Pat. No. 6,166,178. The sequence of a full-length native hTRT has been deposited in GenBank (Accession No. AF015950), and plasmid and phage vectors having hTRT coding sequences have been deposited with the American Type Culture Collection, Rockville, Md. (accession numbers 209024, 209016, and 98505). Nonhuman TRT polypeptides (i.e., hTRT homologs) are described in U.S. patent applications Ser. Nos. 08/974,584, 08/974,549, 08/915,503, 08/912,951. hTRT polypeptides that may be used in the present invention include, in addition to the hTRT polypeptides having amino acid sequences described in the aforecited references and deposits, other naturally occurring variants, including allelic variants and processing variants. As described in detail in patent applications (e.g., U.S. Ser. Nos. 08/912,951 and 08/974,549), it is well within the ability of one of skill to obtain naturally occurring hTRT variants or derivatives, and non-human homologs using the above-mentioned sequences and reagents and using, e.g., standard molecular biological techniques. In certain embodiments of the invention, a hTRT polypeptide or variant (or gene or cDNA encoding such a variant) characteristic of a particular subject (e.g., expressed in tumor cells from the subject) or characteristic of a particular tumor type is used. Such tumor or subject-specific hTRT can be obtained using standard methods, e.g., cloning using hTRT PCR primers, purification using anti-hTRT antibodies, and other techniques. Exemplary uses of hTRT polypeptides and polynucleotides, and nonhuman homologs, are described in additional detail in U.S. patent application Ser. No. 08/974,549 (filed Nov. 19, 1997), 08/974,584 (filed Nov. 19, 1997), 08/915,503 (filed Aug. 14, 1997), 08/912,951 (filed Aug. 14, 1997), 08/911,312 (filed Aug. 14, 1997), 08/854,050 (filed May 9, 1997) U.S. Pat. No. 6,261,836, Ser. No. 08/851,843, (filed May 6, 1997), U.S. Pat. No. 6,093,809, Ser. No. 08/846,017 (filed Apr. 25, 1997) abandoned, 08/844,419 (filed Apr. 18, 1996), abandoned 08/724,643 (filed Oct. 1, 1996) abandoned, and Ser. No. 08/979,742 (filed Nov. 26, 1997), abandoned Each of the aforementioned patent applications is explicitly incorporated herein by reference in its entirety and for all purposes.

A “dendritic cell” (DC) is an antigen presenting cell (APC) with a characteristic morphology including lamellipodia extending from the dendritic cell body in several directions. Several phenotypic criteria are also typical, including high levels of MHC molecules and costimulatory molecules, a lack of markers specific for granulocytes, NK cells, B lymphocytes, and T lymphocytes, but can vary depending on the source of the dendritic cell. DCs are able to initiate antigen specific primary T lymphocyte responses in vitro and in vivo, and direct a strong mixed leukocyte reaction (MLR) compared to peripheral blood leukocytes, splenocytes, B cells and monocytes. DCs can be derived from a hematopoietic stem cell, e.g., a CD34⁺ precursor cell. Dendritic cells are described generally by Steinman, 1991, Annu Rev Immunol. 9:271-96.

A cell is “transduced” with a selected nucleic acid when the nucleic acid is translocated into the cell. A cell is “stably transduced” with a selected nucleic acid when the selected nucleic acid is replicated and passed on to progeny cells. A cell is “transformed” with a selected nucleic acid when the selected nucleic acid is integrated into the cell's genome.

A “TRT expression cassette” is a nucleic acid construct, generated recombinantly or synthetically, that includes a nucleic acid encoding a TRT polypeptide or fragment, and a promoter. In some embodiments, the expression cassette also includes other genetic elements, e.g., an origin of replication, and/or chromosome integration elements such as retroviral LTRs. The TRT expression cassette may be plasmid, virus genome, nucleic acid fragment, or the like.

The term “recombinant” has its usual meaning in the art. Thus, a recombinant polynucleotide is a polynucleotide synthesized or otherwise manipulated in vitro (e.g., using molecular biological techniques), and is typically linked to sequence (e.g., a heterologous promoter, vector sequence or other sequence) with which it is not normally linked in nature and/or comprises mutations (e.g., deletions) compared to naturally occurring forms; a “recombinant polypeptide” is a polypeptide that is produced by expression of a recombinant nucleotide; and a “recombinant cell” is a cell comprising a recombinant polynucleotide.

The terms “activation” or “activating,” when used in reference to a T lymphocyte, has the ordinary meaning in the art of immunology and refers to characteristic changes (e.g., calcium ion influx, tyrosine kinase activation) that follow ligand-receptor interactions between a T lymphocyte and antigen presenting cell. T cell activation ordinarily results in clonal expansion of antigen-reactive T lymphocytes.

II. Introduction

The methods and reagents of the invention are useful for eliciting an in vivo immune response to telomerase, a telomerase protein, and/or a cell expressing telomerase or a telomerase protein. In particular, the methods and reagents of the invention are used to treat or prevent diseases or conditions related to cell proliferation, such as cancers.

In humans and other mammals, many cells that proliferate indefinitely, such as cancer cells, are characterized by the expression of the endogenous telomerase reverse transcriptase (TRT) gene and the presence of detectable telomerase activity. In contrast, most normal somatic cells in mammals have no or very low levels of TRT expression. Thus, by eliciting a specific immune response to TRT or to TRT-expressing cells, it is possible to selectively target proliferating cells for immunological destruction. Reagents, such as the dendritic cells described infra, that induce differentiation and proliferation of T lymphocytes that specifically target telomerase expressing cells may be used for the prevention or treatment of cancer. Induction of an anti-TRT immune response in a human or nonhuman subject will inhibit growth of a tumor in the subject, and/or result in regression of the tumor. The methods and reagents (e.g., cells) of the invention may also be used prophylactically, to elicit an immune response that decreases a subject's risk of developing a cancer.

According to the present invention, an immune response in a subject may be elicited by administration of TRT proteins and fragments and derivatives thereof, polynucleotides encoding such TRT proteins, fragments, and derivatives, and antigen presenting cells (e.g., dendritic cells) comprising the aforementioned polypeptide and polynucleotide reagents, e.g., dendritic cells displaying TRT antigens in the context of peptide/MHC complexes. The immune response that is evoked may be primarily humoral (i.e., antibody meditated), primarily cell-mediated (e.g., cytotoxic T-lymphocyte-mediated), or have both humoral and cellular components. Alternatively, T lymphocytes may be activated ex vivo and administered to a subject.

Thus, in various aspects of the invention, the immune response to TRT or a TRT-expressing cell is elicited by methods including one or more of the steps of (1) administering to a subject an antigen presenting cell (APC) that presents a TRT antigenic peptide; (2) administering to a subject T-lymphocytes that recognize a TRT peptide/MHC complex; (3) administering an immunogenic amount of a polynucleotide encoding a TRT protein, polypeptide, or fragment; (4) administering an immunogenic amount of a TRT protein, polypeptide, or fragment. The polynucleotide of (3) or polypeptide. of (4) are usually administered in an amount capable of inducing a Class I MHC-restricted cytotoxic T-lymphocyte response against cells expressing a TRT protein or, alternatively, in an amount capable of inducing the production of antibodies by the subject.

II. The Use of Antigen Presenting Cell (APCs) to Elicit an Anti-TRT Immune Response

In one embodiment of the invention, antigen presenting cells (APCs) are used to activate T lymphocytes in vivo or ex vivo, to elicit an immune response against TRT-expressing cells. APCs are highly specialized cells, including macrophages, monocytes, and dendritic cells (DCs), that can process antigens and display their peptide fragments on the cell surface together with molecules required for lymphocyte activation Generally, however, dendritic cells are superior to other antigen presenting cells for inducing a T lymphocyte mediated response (e.g., a primary immune response). DCs may be classified into subgroups, including, e.g., follicular dendritic cells, Langerhans dendritic cells, and epidermal dendritic cells.

DCs have been shown to be potent simulators of both T helper (Th) and cytotoxic T lymphocyte (CTL) responses. See Schuler et al., 1997, Int. Arch. Allergy Immunol. 112:317-22. In vivo, DCs display antigenic peptides in complexes with MHC class I and MHC class II proteins, The loading of MHC class I molecules usually occurs when cytoplasmic proteins (including proteins such as TRT that are ultimately transported to the nucleus) are processed and transported into the secretory compartments containing the MHC class I molecules. MHC Class II proteins are normally loaded in vivo following sampling (e.g., by endocytosis) by APCsof the extracellular milieu. DCs migrate to lymphoid organs where they induce proliferation and differentiation of antigen-specific T lymphocytes, i.e., Th cells that recognize the peptide/MHC Class II complex and CTLs that recognize the peptide/MHC Class I complex. An introduction to T lymphocytes and cell mediated immunity is found in Paul, 1993, FUNDAMENTAL IMMUNOLOGY, THIRD EDITION Raven Press, New York, N.Y. and the references cited therein.

It is now understood that DCs (or DC precursor cells) can be exposed to antigenic peptide fragments ex vivo (referred to as “antigen pulsing”), or genetically modified ex vivo to express a desired antigen, and subsequently administered to a patient to induce an anti-antigen immune response. Alternatively, the pulsed or genetically modified DCs can be cultured ex vivo with T lymphocytes (e.g., HLA-matched T lymphocytes) to activate those T cells that specific for the selected antigen. Of particular relevance to the present invention, antigen-laden DC may be used to boost host defense against tumors (see, e.g., Hsu, et al., 1996, Nature Med. 2:52-58; Young et al., 1996, J. Exp Med. 183:7-11; McArthur et al., 1998, J. Immunother. 21:41-47; Tuting et al., 1997, Eur. J. Immunol. 27:2702-2707; Nair et al., 1997, Int. J. Cancer 70:706-715). It will be appreciated that is not necessary that the target antigen (e.g., target “tumor” antigen) be expressed naturally on the cell surface, because cytoplasmic proteins and nuclear proteins, such as TRT, are normally processed, attached to MHC-encoded products intracellularly, and translocated to the cell surface as a peptide/MHC complex.

In one aspect, the present invention relates to the use of polypeptides and polynucleotides encoding TRT (especially human hTRT), and antigen presenting cells (especially dendritic cells), to elicit an immune response against TRT-expressing cells, such as cancer cells, in a subject Typically, this involves (1) isolating a hematopoietic stem cells, (2) genetically modifying the cells to express a TRT polypeptide, (3) differentiating the precursor cells into DCs and (4) administering the DCs to the subject (e.g., human patient). In an alternative embodiment, the process involves (1) isolating DCs (or isolation and differentiation of DC precursor cells) (2) pulsing the cells with TRT peptides, and (3) administering the DCs to the subject These approaches are discussed in greater detail, infra. In a related embodiment, the TRT pulsed or expressing DCs of the invention are used to activate T lymphocytes ex vivo. It will be recognize however, that many variations of each of the procedures described infra are known to those of skill (see, e.g., WO97/29182; WO 97/04802; WO 97/22349; WO 96/23060; WO 98/01538; Hsu et al., 1996, Nature Med. 2:52-58), and that still other variations may be discovered in the future.

A. Genetic Modification of Dendritic Cell Precursor

In one embodiment, DC stem cells are isolated for transduction with a TRT-encoding polynucleotide, and induced to differentiate into dendritic cells. The genetically modified DCs express the TRT polypeptide, and display peptide fragments on the cell surface.

(1) Isolation of DC Precursor Cells

Many methods are known for isolating DC precursor cells suitable for transfection with a recombinant TRT-encoding nucleic acid. Human hematopoietic progenitor and stem cells are characterized by the presence of a CD34 surface membrane antigen, which may be used in purification. In one embodiment, for example, human hematopoietic stem cells are obtained by bone marrow aspiration, and the bone marrow mononuclear cells are separated from the other components by means of Ficol density gradient centrifugation and adherence to plastic. The light density, non-adherent cells are obtained and further selected using an anti-CD34 antibody (preferably monoclonal) by standard methods (e.g., incubation of cells with the anti-CD34 antibody, subsequent binding to an immobilized secondary antibody, and removal of nonbound components; see, e.g., Harlow and Lane, 1988, ANTIBODIES: A LABORATORY MANUAL, Cold Spring Harbor Laboratory, New York) Alternatively, cells can be obtained by leukapheresis of peripheral blood and anti-CD34 chromatography (see, e.g., Reeves et al, 1996, Cancer Res. 56:5672-77).

(2) Genetic Modification of Cells to Express a TRT Polypeptide

In one embodiment of the invention, the DC or DC precursor cell is genetically modified to express a TRT polypeptide (e.g., transduced ex vivo with a polynucleotide encoding TRT). Exogenous TRT-encoding polynucleotides may be incorporated into DC as TRT expression cassettes using methods such as those described infra. Typically the DC is transformed with an expression cassette comprising a region encoding a TRT polypeptide (or one or more fragments thereof). Upon expression of the TRT expression cassette in the cell, the TRT polypeptide is processed into antigenic peptides expressed on the surface of the DC as complex with MHC class I and II surface molecules. Typically the TRT expression cassette includes an operably linked promoter (to drive expression of the TRT coding sequences). Usually a strong promoter such as a t-RNA pol III promoter, or a pol II promoter with strong constitutive expression is used. Suitable promoters include the constitutive adenovirus major late promoter, the dexamethasone-inducible MMIV promoter, the SV40 promoter, the MRP polIII promoter, the constitutive MPSV promoter, the tetracycline-inducible CMV promoter (such as the human immediate-early CMV promoter), the constitutive CMV promoter, and promoter-enhancer combinations known in the art. In alternative embodiments, the TRT coding sequence is introduced into the DC precursor without a linked promoter. In such a case the TRT transcription is directed by an endogenous promoter (e.g., following integration of the TRT coding sequence into the cell chromosome) or a separately introduced promoter (e.g., that becomes linked by recombination). Often the TRT expression cassette is contained in an expression vector such as a plasmid or viral vector, which may also include other elements, e.g., an origin of replication, chromosome integration elements such as retroviral LTRs, and/or selection (e.g., drug resistance) sequences.

In one embodiment all of most (e.g., at least about 60%, at least about 75% or at least about 90%) of the TRT protein is expressed (i.e., coded for) in the TRT expression cassette. In some cases, however, a shorter fragment may be expressed. Usually TRT coding sequence will encode at least about 8, more often 12, still more often at least 30 or at least 50 contiguous TRT amino acid residues.

In some embodiments, the TRT polypeptide expressed has a sequence of a naturally occurring TRT. It will be recognized, however, that the invention is not limited to naturally occurring sequences. As already noted, fragments of naturally occurring TRT proteins may be used; in addition, the expressed TRT polypeptide may comprise mutations such as deletions, insertions, or amino acid substitutions when compared to a naturally occurring TRT polypeptide, so long as at least one TRT peptide epitope can be processed by the DC and presented on a MHC class I or II surface molecule. It will be appreciated that it may sometimes be desirable to use TRT sequences other than “wild type,” in order to, for example, increase antigenicity of the TRT peptide or to increase TRT peptide expression levels. In some embodiments, the introduced TRT sequences encode TRT variants such as polymorphic variants (e.g., a variant expressed by a particular human patient) or variants characteristic of a particular cancer (e.g., a cancer in a particular patient).

The TRT expression sequence may be introduced (transduced) into DCs or stem cells in any of a variety of standard methods, including transfection, recombinant vaccinia viruses, adeno-associated viruses (AAVs), and retroviruses (see, e.g., Reeves et al., 1996, Cancer Res. 56:5672; Brossart et al., 1997, J. Immunol. 158:3270; Ribas et al., 1997, Canc. Res. 57:2865; Carter et al., 1993, WO 93/24641; Kotin, 1994, Human Gene Therapy 5:793-801; Specht et al., 1997, J. Exp. Med. 186:1213-1221), particle-mediated gene transfer technology (Tuting et al., 1997, Eur J Immunol., 27:2702-2707), or other conventional methods for transforming stem cells are known (e.g., calcium phosphate precipitation; see e.g., Krieger, 1990, GENE TRANSFER AND EXPRESSION—A LABORATORY MANUAL, Stockton Press, New York, N.Y.; Sambrook et al., 1989, MOLECULAR CLONING A LABORATORY MANUAL 2ND ED, Vol. 1-3; and Ausubel et al., eds, 1997, CURRENT PROTOCOLS IN MOLECULAR BIOLOGY, John Wiley & Sons, Inc.). Alternately, TRT-encoding polynucleotide can be packaged into viral particles using packaging cell lines, which are incubated with the DC stem cells.

(3) Differentiation of Precursor Cells into DCs

The TRT-peptide expressing hematopoietic progenitor cells described supra are induced to differentiate into DCs by conventional methods, e.g., by exposure to cytokines such as granulocyte macrophage colony-stimulating factor (GM-CSF), flt-3 ligand, tumor necrosis factor alpha c-kit ligand (also called steel factor or mast cell factor). The addition of interleukin-4 (IL-4) to monocyte cultures is reported to help direct cells to develop as dendritic cells, and TNF-alpha, when mixed with undifferentiated stem cells, increases the likelihood that the stem cells will develop as dendritic cells (see Szaboles et al., 1995, J. Immunol. 154:5851-5861). Alternatively, calcium ionophore is used to stimulate the maturation of isolated monocytes into dendritic cells (U.S. Pat. No. 5,643,786). In one embodiment, DCs are obtained from CD34+ hematopoietic progenitor cells from the blood (e.g., of cancer patients) according to the method described by Bernhard et al., 1995, Cancer Res. 55:1099-104. A DC maturation factor may be used to cause “immature DCs” to stably express dendritic cell characteristics (e.g., dendritic cell markers p55 and CD83; see WO 97/29182). Alternatively, immature DCs may be used to activate T cells (Koch et al., 1995, J. Immunol. 155:93-100).

The culture of cells such as those used in conjunction with the present invention, including stem cells and dendritic cells is well known in the art (see, e.g., Freshney, 1994, CULTURE OF ANIMAL CELLS, A MANUAL OF BASIC TECHNIQUE, THIRD EDITION Wiley-Liss, New York).

(4) Administering the DCs to the Subject (e.g. Human Patient

The transformed DCs of the invention are introduced into the subject (e.g., human patient) where they induce a immune response. Typically the immune response includes a CTL response against target cells bearing TRT antigenic peptides (e.g., in a MHC class I/peptide complex). These target cells are typically cancer cells.

When the DCs of the invention are to be administered to a patient, they are preferably isolated from, or derived from precursor cells from, that patient (i.e., the DCs are administered to an autologous patient). However, the cells may be infused into HLA-matched allogeneic, or HLA-mismatched allogenic patients. In the latter case, immunosuppressive drugs may be administered to the recipient.

The cells are administered in any suitable manner, preferably with a pharmaceutically acceptable carrier (e.g., saline). Usually administration will be intravenous, but intra-articular, intramuscular, intradermal, intraperitoneal, and subcutaneous routes are also acceptable. Administration (i.e., immunization) may be repeated at time intervals. Infusions of DC may be combined with administration of cytokines that act to maintain DC number and activity (e.g., GM-CSF, IL-12)

The dose administered to a patient, in the context of the present invention should be sufficient to induce an immune response as detected by assays which measure T cell proliferation, T lymphocyte cytotoxicity, and/or effect a beneficial therapeutic response in the patient over time, e.g., to inhibit growth of cancer cells or result in reduction in the number of cancer cells or the size of a tumor. Typically, 10⁶ to 10⁹ or more DCs are infused, if available.

B. Peptide Pulsing of Dendritic Cells

In a related embodiment of the invention, DCs are obtained (either from a patient or by in vitro differentiation of precursor cells) and pulsed with antigenic peptides having a sequence of TRT (e.g., hTRT). The pulsing results in the presentation of TRT peptides onto the surface MHC molecules of the cells. The TRT-peptide/MHC complexes displayed on the cell surface are capable of inducing a MHC-restricted cytotoxic T-lymphocyte response against target cells expressing TRT polypeptides (e.g., cancer cells).

(1) Isolation of DCs

DCs can be obtained by isolating DC precursor cells and inducing them to differentiate into DCs, as described supra. Alternatively, DCs may be isolated from both lymphoid and non-lymphoid tissues; typically they are purified from peripheral blood. Methods for isolation of human DCs from blood include apheresis followed by procedures involving density gradient methods, positive selection (e.g., affinity chromatography with antibodies directed to DC surface markers), negative selection, or combinations thereof (see, e.g., WO97122349; WO95134638; WO98/01538; WO94/02156).

DC may be isolated from a normal human or from a patient suffering from a disease. In either case, individuals may be treated with colony stimulating factors to increase their number of DC prior to isolation. For example, GM-CSF, may be infused into an individual at 250 μg/m²/day for several days up to three weeks intravenously prior to obtaining the peripheral blood mononuclear leukocytes (PBML) for the purification of DC. This procedure may increase the yield of DC for antigen pulsing and subsequent

It will be appreciated that, in one embodiment of the invention, “immortalized” or “extended life span dendritic cells” are used. Immortalized DCs may be prepared according to the methods of copending applications U.S. Ser. No. 08/912,951 and 08/974,549. In an alternative embodiment, DCs transformed with Epstein-Barr virus (see, WO 97/04802), retroviral vectors containing an oncogene (see, e.g, WO 94/28113) and the like (U.S. Pat. No. 5,648,219) may be used

(2) Pulsing DCs with TRT Peptides

DCs are exposed ex vivo to TRT antigens, and allowed to process the antigen so that TRT epitopes are presented on the surface of the cell in the context of a MHC class I (or MHC class II) complex. This procedure is referred to as “antigen pulsing.” The “pulsed DCs” may then be used to activate T lymphocytes.

The TRT peptide antigens used for pulsing DCs comprise at least one linear epitopes derived from the TRT protein. TRT proteins or substantial fragments thereof may be used, as they will be taken up and processed by the DCs. Alternatively, short “peptides” may be administered to the DCs.

When TRT peptides are used for pulsing, they will usually have at least about 6 or 8 amino acids and fewer than about 30 amino acids or fewer than about 50 amino acid residues in length In one embodiment, the immunogenic TRT peptide has between about 8 and 12 amino acids. A mixture of hTRT protein fragments may be used; alternatively a particular peptide of defined sequence may be used. The TRT peptide antigens may be produced by de novo peptide synthesis, enzymatic digestion of purified or recombinant hTRT, by purification of telomerase from a natal source (e.g., a patient or tumor cells from a patient), or expression of a recombinant polynucleotide encoding a hTRT fragment.

It has been found that the various class I MHC alleles bind peptides having, from N-terminus to C-terminus, first, second and/or third conserved amino acid residues separated by a certain number of amino acids. The binding motifs for several human HLA-A alleles are provided in WO 94/03205. Thus, in one embodiment of the invention, the TRT fragment or peptide comprises at least one linear TRT epitope having a class I MHC binding motif, and, in particular, an HLA-A1 binding motif, an HLA-A2.1 binding motif, an HLA-A3.2 binding motif an HLA-A11 binding motif, an HLA-A24.1 binding motif or an HLA-B7 binding motif Provided with the nucleic acid and protein sequences of a TRT, such as the hTRT sequences provided in FIG. 1 and FIG. 2, it is within the ability of one of ordinary skill to identify and produce various large or small polypeptides or peptides that comprise particular HLA binding motifs. If desired, a mixture of TRT peptides may be used, so that a wide variety of HLA binding motifs are represented.

The amount of TRT antigen used for pulsing DC will depend on the nature, size and purity of the peptide or polypeptide. Typically, from about 0.05 μg/ml to about 1 mg/ml, most often from about 1 to about 100 μg/ml of TRT peptide is used. After adding the TRT peptide antigen(s) to the cultured DC, the cells are then allowed sufficient time to take up and process the antigen and express antigen peptides on the cell surface in association with either class I or class II MHC. Typically this occurs in about 18-30 hours, most often about 24 hours. In one exemplary embodiment enriched DC are resuspended (10⁶ cells/ml) in RPMI media (Gibco) and cultured with (50 ug/ml) hTRT peptide antigens overnight under standard conditions (e.g., 37° C. humidified incubator/5% CO2).

(3) Administering the DCs to the Subject

The pulsed DC are washed in physiologic saline and administered to a subject as described supra, Section (A)(4).

C) Administration of TRT-Reactive T Lymphocytes

Antigen-specific T lymphocytes may be prepared ex vivo by collecting naive T lymphocytes from an individual (e.g., CD8+ T lymphocytes), contacting them with the DCs of the invention (e.g., TRT transformed or pulsed DCs) so that TRT-reactive T lymphocytes proliferate. In an alternative embodiment, the DCs are pulsed with TRT antigens at the time of co-culture with T lymphocytes. The expanded TRT-reactive T lymphocyte population may then be administered to the individual, or may be used for in vitro assays. When administered to a patient, the ex vivo activated-T lymphocytes are cytotoxic against target cells bearing TRT antigenic peptides, such as cancer cells (see, e.g., WO 94/ 02156).

Several techniques are known for isolating T lymphocytes. In one method, Ficoll-Hypaque density gradient centrifugation is used to separate PBMC from red blood cells and neutrophils according to established procedures. Cells are washed with AIM-V (GIBCO) supplemented with 2 mM glutamine, 10 μg/ml gentamicin sulfate, 50 μg/ml streptomycin and 1% fetal bovine serum). Enrichment for T lymphocytes is performed by negative or positive selection with appropriate monoclonal antibodies (e.g., anti-CD2, CD3, CD4, CD5 and CD8) coupled to columns or magnetic beads according to standard techniques. Alternatively, fluorescence-activated cell sorting is used. An aliquot of cells is analyzed for cell surface phenotype including CD4, CD8, CD3 and CD 14. Cells are washed and resuspended at a concentration of 5×10⁵ cells per ml of AIM-V supplemented as above and containing 5% FBS and 100 U/ml recombinant IL-2. The T lymphocytes are then cultured with pulsed or genetically modified DCs, optionally in the presence of low doses of IL-4 and IL-2.

The activated T lymphocytes can then be administered to a subject (e.g., infused) as described for DCs, supra. The expanded T lymphocytes may be administered alone, or in combination with lymphokines such as IL-2 and/or IL-4.

IV. IN VITRO ASSAYS

The present invention provides commercially valuable assays, e.g., for identifying TRT-expressing cells. In the assays of the invention, dendritic cells are transformed with a TRT encoding nucleic acid or pulsed with a TRT peptide. The DC is used to activate isolated T lymphocytes, which are then tested for cytotoxic activity against a class of cells though to TRT. Cytotoxicity (e.g., as indicated in a standard assays such as a “⁵¹Cr release assay,” infra) indicates that the cells express TRT is amounts sufficient to mediate a T lymphocyte recognition of the cell. This provides investigators with an assay for TRT-expressing cells.

To demonstrate that CTL have cytolytic activity against a cell (e.g., a cell expressing TRT, such as a cancer cell) the target antigen-presenting cells and effector CTL cells are mixed in culture and target cell lysis is observed. Any suitable method for measuring cell lysis can be used by one skilled in the art. For example, a radioactivity release assay can be used to measure lysis of the target cells. For example, the target cells are labeled with radioactive reagents such as ⁵¹Cr, which are taken up by live cells. Following labeling, the target cells are washed and mixed with specific CTLs. Supernatants are harvested after a suitable time and counted to determine the percent radioactivity release. Other methods to determine the amount of cell lysis include trypan blue exclusion, in which living cells that exclude the dye are counted and compared to a control sample of non-presenting cells treated in the same manner.

All publications and patent documents cited in this application are incorporated by reference in their entirety for all purposes to the same extent as if each individual publication or patent document were so individually denoted.

2 1 4015 DNA Homo sapiens CDS (56)..(3454) human telomerase reverse transcriptase (hTRT) 1 gcagcgctgc gtcctgctgc gcacgtggga agccctggcc ccggccaccc ccgcg atg 58 Met 1 ccg cgc gct ccc cgc tgc cga gcc gtg cgc tcc ctg ctg cgc agc cac 106 Pro Arg Ala Pro Arg Cys Arg Ala Val Arg Ser Leu Leu Arg Ser His 5 10 15 tac cgc gag gtg ctg ccg ctg gcc acg ttc gtg cgg cgc ctg ggg ccc 154 Tyr Arg Glu Val Leu Pro Leu Ala Thr Phe Val Arg Arg Leu Gly Pro 20 25 30 cag ggc tgg cgg ctg gtg cag cgc ggg gac ccg gcg gct ttc cgc gcg 202 Gln Gly Trp Arg Leu Val Gln Arg Gly Asp Pro Ala Ala Phe Arg Ala 35 40 45 ctg gtg gcc cag tgc ctg gtg tgc gtg ccc tgg gac gca cgg ccg ccc 250 Leu Val Ala Gln Cys Leu Val Cys Val Pro Trp Asp Ala Arg Pro Pro 50 55 60 65 ccc gcc gcc ccc tcc ttc cgc cag gtg tcc tgc ctg aag gag ctg gtg 298 Pro Ala Ala Pro Ser Phe Arg Gln Val Ser Cys Leu Lys Glu Leu Val 70 75 80 gcc cga gtg ctg cag agg ctg tgc gag cgc ggc gcg aag aac gtg ctg 346 Ala Arg Val Leu Gln Arg Leu Cys Glu Arg Gly Ala Lys Asn Val Leu 85 90 95 gcc ttc ggc ttc gcg ctg ctg gac ggg gcc cgc ggg ggc ccc ccc gag 394 Ala Phe Gly Phe Ala Leu Leu Asp Gly Ala Arg Gly Gly Pro Pro Glu 100 105 110 gcc ttc acc acc agc gtg cgc agc tac ctg ccc aac acg gtg acc gac 442 Ala Phe Thr Thr Ser Val Arg Ser Tyr Leu Pro Asn Thr Val Thr Asp 115 120 125 gca ctg cgg ggg agc ggg gcg tgg ggg ctg ctg ctg cgc cgc gtg ggc 490 Ala Leu Arg Gly Ser Gly Ala Trp Gly Leu Leu Leu Arg Arg Val Gly 130 135 140 145 gac gac gtg ctg gtt cac ctg ctg gca cgc tgc gcg ctc ttt gtg ctg 538 Asp Asp Val Leu Val His Leu Leu Ala Arg Cys Ala Leu Phe Val Leu 150 155 160 gtg gct ccc agc tgc gcc tac cag gtg tgc ggg ccg ccg ctg tac cag 586 Val Ala Pro Ser Cys Ala Tyr Gln Val Cys Gly Pro Pro Leu Tyr Gln 165 170 175 ctc ggc gct gcc act cag gcc cgg ccc ccg cca cac gct agt gga ccc 634 Leu Gly Ala Ala Thr Gln Ala Arg Pro Pro Pro His Ala Ser Gly Pro 180 185 190 cga agg cgt ctg gga tgc gaa cgg gcc tgg aac cat agc gtc agg gag 682 Arg Arg Arg Leu Gly Cys Glu Arg Ala Trp Asn His Ser Val Arg Glu 195 200 205 gcc ggg gtc ccc ctg ggc ctg cca gcc ccg ggt gcg agg agg cgc ggg 730 Ala Gly Val Pro Leu Gly Leu Pro Ala Pro Gly Ala Arg Arg Arg Gly 210 215 220 225 ggc agt gcc agc cga agt ctg ccg ttg ccc aag agg ccc agg cgt ggc 778 Gly Ser Ala Ser Arg Ser Leu Pro Leu Pro Lys Arg Pro Arg Arg Gly 230 235 240 gct gcc cct gag ccg gag cgg acg ccc gtt ggg cag ggg tcc tgg gcc 826 Ala Ala Pro Glu Pro Glu Arg Thr Pro Val Gly Gln Gly Ser Trp Ala 245 250 255 cac ccg ggc agg acg cgt gga ccg agt gac cgt ggt ttc tgt gtg gtg 874 His Pro Gly Arg Thr Arg Gly Pro Ser Asp Arg Gly Phe Cys Val Val 260 265 270 tca cct gcc aga ccc gcc gaa gaa gcc acc tct ttg gag ggt gcg ctc 922 Ser Pro Ala Arg Pro Ala Glu Glu Ala Thr Ser Leu Glu Gly Ala Leu 275 280 285 tct ggc acg cgc cac tcc cac cca tcc gtg ggc cgc cag cac cac gcg 970 Ser Gly Thr Arg His Ser His Pro Ser Val Gly Arg Gln His His Ala 290 295 300 305 ggc ccc cca tcc aca tcg cgg cca cca cgt ccc tgg gac acg cct tgt 1018 Gly Pro Pro Ser Thr Ser Arg Pro Pro Arg Pro Trp Asp Thr Pro Cys 310 315 320 ccc ccg gtg tac gcc gag acc aag cac ttc ctc tac tcc tca ggc gac 1066 Pro Pro Val Tyr Ala Glu Thr Lys His Phe Leu Tyr Ser Ser Gly Asp 325 330 335 aag gag cag ctg cgg ccc tcc ttc cta ctc agc tct ctg agg ccc agc 1114 Lys Glu Gln Leu Arg Pro Ser Phe Leu Leu Ser Ser Leu Arg Pro Ser 340 345 350 ctg act ggc gct cgg agg ctc gtg gag acc atc ttt ctg ggt tcc agg 1162 Leu Thr Gly Ala Arg Arg Leu Val Glu Thr Ile Phe Leu Gly Ser Arg 355 360 365 ccc tgg atg cca ggg act ccc cgc agg ttg ccc cgc ctg ccc cag cgc 1210 Pro Trp Met Pro Gly Thr Pro Arg Arg Leu Pro Arg Leu Pro Gln Arg 370 375 380 385 tac tgg caa atg cgg ccc ctg ttt ctg gag ctg ctt ggg aac cac gcg 1258 Tyr Trp Gln Met Arg Pro Leu Phe Leu Glu Leu Leu Gly Asn His Ala 390 395 400 cag tgc ccc tac ggg gtg ctc ctc aag acg cac tgc ccg ctg cga gct 1306 Gln Cys Pro Tyr Gly Val Leu Leu Lys Thr His Cys Pro Leu Arg Ala 405 410 415 gcg gtc acc cca gca gcc ggt gtc tgt gcc cgg gag aag ccc cag ggc 1354 Ala Val Thr Pro Ala Ala Gly Val Cys Ala Arg Glu Lys Pro Gln Gly 420 425 430 tct gtg gcg gcc ccc gag gag gag gac aca gac ccc cgt cgc ctg gtg 1402 Ser Val Ala Ala Pro Glu Glu Glu Asp Thr Asp Pro Arg Arg Leu Val 435 440 445 cag ctg ctc cgc cag cac agc agc ccc tgg cag gtg tac ggc ttc gtg 1450 Gln Leu Leu Arg Gln His Ser Ser Pro Trp Gln Val Tyr Gly Phe Val 450 455 460 465 cgg gcc tgc ctg cgc cgg ctg gtg ccc cca ggc ctc tgg ggc tcc agg 1498 Arg Ala Cys Leu Arg Arg Leu Val Pro Pro Gly Leu Trp Gly Ser Arg 470 475 480 cac aac gaa cgc cgc ttc ctc agg aac acc aag aag ttc atc tcc ctg 1546 His Asn Glu Arg Arg Phe Leu Arg Asn Thr Lys Lys Phe Ile Ser Leu 485 490 495 ggg aag cat gcc aag ctc tcg ctg cag gag ctg acg tgg aag atg agc 1594 Gly Lys His Ala Lys Leu Ser Leu Gln Glu Leu Thr Trp Lys Met Ser 500 505 510 gtg cgg gac tgc gct tgg ctg cgc agg agc cca ggg gtt ggc tgt gtt 1642 Val Arg Asp Cys Ala Trp Leu Arg Arg Ser Pro Gly Val Gly Cys Val 515 520 525 ccg gcc gca gag cac cgt ctg cgt gag gag atc ctg gcc aag ttc ctg 1690 Pro Ala Ala Glu His Arg Leu Arg Glu Glu Ile Leu Ala Lys Phe Leu 530 535 540 545 cac tgg ctg atg agt gtg tac gtc gtc gag ctg ctc agg tct ttc ttt 1738 His Trp Leu Met Ser Val Tyr Val Val Glu Leu Leu Arg Ser Phe Phe 550 555 560 tat gtc acg gag acc acg ttt caa aag aac agg ctc ttt ttc tac cgg 1786 Tyr Val Thr Glu Thr Thr Phe Gln Lys Asn Arg Leu Phe Phe Tyr Arg 565 570 575 aag agt gtc tgg agc aag ttg caa agc att gga atc aga cag cac ttg 1834 Lys Ser Val Trp Ser Lys Leu Gln Ser Ile Gly Ile Arg Gln His Leu 580 585 590 aag agg gtg cag ctg cgg gag ctg tcg gaa gca gag gtc agg cag cat 1882 Lys Arg Val Gln Leu Arg Glu Leu Ser Glu Ala Glu Val Arg Gln His 595 600 605 cgg gaa gcc agg ccc gcc ctg ctg acg tcc aga ctc cgc ttc atc ccc 1930 Arg Glu Ala Arg Pro Ala Leu Leu Thr Ser Arg Leu Arg Phe Ile Pro 610 615 620 625 aag cct gac ggg ctg cgg ccg att gtg aac atg gac tac gtc gtg gga 1978 Lys Pro Asp Gly Leu Arg Pro Ile Val Asn Met Asp Tyr Val Val Gly 630 635 640 gcc aga acg ttc cgc aga gaa aag agg gcc gag cgt ctc acc tcg agg 2026 Ala Arg Thr Phe Arg Arg Glu Lys Arg Ala Glu Arg Leu Thr Ser Arg 645 650 655 gtg aag gca ctg ttc agc gtg ctc aac tac gag cgg gcg cgg cgc ccc 2074 Val Lys Ala Leu Phe Ser Val Leu Asn Tyr Glu Arg Ala Arg Arg Pro 660 665 670 ggc ctc ctg ggc gcc tct gtg ctg ggc ctg gac gat atc cac agg gcc 2122 Gly Leu Leu Gly Ala Ser Val Leu Gly Leu Asp Asp Ile His Arg Ala 675 680 685 tgg cgc acc ttc gtg ctg cgt gtg cgg gcc cag gac ccg ccg cct gag 2170 Trp Arg Thr Phe Val Leu Arg Val Arg Ala Gln Asp Pro Pro Pro Glu 690 695 700 705 ctg tac ttt gtc aag gtg gat gtg acg ggc gcg tac gac acc atc ccc 2218 Leu Tyr Phe Val Lys Val Asp Val Thr Gly Ala Tyr Asp Thr Ile Pro 710 715 720 cag gac agg ctc acg gag gtc atc gcc agc atc atc aaa ccc cag aac 2266 Gln Asp Arg Leu Thr Glu Val Ile Ala Ser Ile Ile Lys Pro Gln Asn 725 730 735 acg tac tgc gtg cgt cgg tat gcc gtg gtc cag aag gcc gcc cat ggg 2314 Thr Tyr Cys Val Arg Arg Tyr Ala Val Val Gln Lys Ala Ala His Gly 740 745 750 cac gtc cgc aag gcc ttc aag agc cac gtc tct acc ttg aca gac ctc 2362 His Val Arg Lys Ala Phe Lys Ser His Val Ser Thr Leu Thr Asp Leu 755 760 765 cag ccg tac atg cga cag ttc gtg gct cac ctg cag gag acc agc ccg 2410 Gln Pro Tyr Met Arg Gln Phe Val Ala His Leu Gln Glu Thr Ser Pro 770 775 780 785 ctg agg gat gcc gtc gtc atc gag cag agc tcc tcc ctg aat gag gcc 2458 Leu Arg Asp Ala Val Val Ile Glu Gln Ser Ser Ser Leu Asn Glu Ala 790 795 800 agc agt ggc ctc ttc gac gtc ttc cta cgc ttc atg tgc cac cac gcc 2506 Ser Ser Gly Leu Phe Asp Val Phe Leu Arg Phe Met Cys His His Ala 805 810 815 gtg cgc atc agg ggc aag tcc tac gtc cag tgc cag ggg atc ccg cag 2554 Val Arg Ile Arg Gly Lys Ser Tyr Val Gln Cys Gln Gly Ile Pro Gln 820 825 830 ggc tcc atc ctc tcc acg ctg ctc tgc agc ctg tgc tac ggc gac atg 2602 Gly Ser Ile Leu Ser Thr Leu Leu Cys Ser Leu Cys Tyr Gly Asp Met 835 840 845 gag aac aag ctg ttt gcg ggg att cgg cgg gac ggg ctg ctc ctg cgt 2650 Glu Asn Lys Leu Phe Ala Gly Ile Arg Arg Asp Gly Leu Leu Leu Arg 850 855 860 865 ttg gtg gat gat ttc ttg ttg gtg aca cct cac ctc acc cac gcg aaa 2698 Leu Val Asp Asp Phe Leu Leu Val Thr Pro His Leu Thr His Ala Lys 870 875 880 acc ttc ctc agg acc ctg gtc cga ggt gtc cct gag tat ggc tgc gtg 2746 Thr Phe Leu Arg Thr Leu Val Arg Gly Val Pro Glu Tyr Gly Cys Val 885 890 895 gtg aac ttg cgg aag aca gtg gtg aac ttc cct gta gaa gac gag gcc 2794 Val Asn Leu Arg Lys Thr Val Val Asn Phe Pro Val Glu Asp Glu Ala 900 905 910 ctg ggt ggc acg gct ttt gtt cag atg ccg gcc cac ggc cta ttc ccc 2842 Leu Gly Gly Thr Ala Phe Val Gln Met Pro Ala His Gly Leu Phe Pro 915 920 925 tgg tgc ggc ctg ctg ctg gat acc cgg acc ctg gag gtg cag agc gac 2890 Trp Cys Gly Leu Leu Leu Asp Thr Arg Thr Leu Glu Val Gln Ser Asp 930 935 940 945 tac tcc agc tat gcc cgg acc tcc atc aga gcc agt ctc acc ttc aac 2938 Tyr Ser Ser Tyr Ala Arg Thr Ser Ile Arg Ala Ser Leu Thr Phe Asn 950 955 960 cgc ggc ttc aag gct ggg agg aac atg cgt cgc aaa ctc ttt ggg gtc 2986 Arg Gly Phe Lys Ala Gly Arg Asn Met Arg Arg Lys Leu Phe Gly Val 965 970 975 ttg cgg ctg aag tgt cac agc ctg ttt ctg gat ttg cag gtg aac agc 3034 Leu Arg Leu Lys Cys His Ser Leu Phe Leu Asp Leu Gln Val Asn Ser 980 985 990 ctc cag acg gtg tgc acc aac atc tac aag atc ctc ctg ctg cag gcg 3082 Leu Gln Thr Val Cys Thr Asn Ile Tyr Lys Ile Leu Leu Leu Gln Ala 995 1000 1005 tac agg ttt cac gca tgt gtg ctg cag ctc cca ttt cat cag caa gtt 3130 Tyr Arg Phe His Ala Cys Val Leu Gln Leu Pro Phe His Gln Gln Val 1010 1015 1020 1025 tgg aag aac ccc aca ttt ttc ctg cgc gtc atc tct gac acg gcc tcc 3178 Trp Lys Asn Pro Thr Phe Phe Leu Arg Val Ile Ser Asp Thr Ala Ser 1030 1035 1040 ctc tgc tac tcc atc ctg aaa gcc aag aac gca ggg atg tcg ctg ggg 3226 Leu Cys Tyr Ser Ile Leu Lys Ala Lys Asn Ala Gly Met Ser Leu Gly 1045 1050 1055 gcc aag ggc gcc gcc ggc cct ctg ccc tcc gag gcc gtg cag tgg ctg 3274 Ala Lys Gly Ala Ala Gly Pro Leu Pro Ser Glu Ala Val Gln Trp Leu 1060 1065 1070 tgc cac caa gca ttc ctg ctc aag ctg act cga cac cgt gtc acc tac 3322 Cys His Gln Ala Phe Leu Leu Lys Leu Thr Arg His Arg Val Thr Tyr 1075 1080 1085 gtg cca ctc ctg ggg tca ctc agg aca gcc cag acg cag ctg agt cgg 3370 Val Pro Leu Leu Gly Ser Leu Arg Thr Ala Gln Thr Gln Leu Ser Arg 1090 1095 1100 1105 aag ctc ccg ggg acg acg ctg act gcc ctg gag gcc gca gcc aac ccg 3418 Lys Leu Pro Gly Thr Thr Leu Thr Ala Leu Glu Ala Ala Ala Asn Pro 1110 1115 1120 gca ctg ccc tca gac ttc aag acc atc ctg gac tgatggccac ccgcccacag 3471 Ala Leu Pro Ser Asp Phe Lys Thr Ile Leu Asp 1125 1130 ccaggccgag agcagacacc agcagccctg tcacgccggg ctctacgtcc cagggaggga 3531 ggggcggccc acacccaggc ccgcaccgct gggagtctga ggcctgagtg agtgtttggc 3591 cgaggcctgc atgtccggct gaaggctgag tgtccggctg aggcctgagc gagtgtccag 3651 ccaagggctg agtgtccagc acacctgccg tcttcacttc cccacaggct ggcgctcggc 3711 tccaccccag ggccagcttt tcctcaccag gagcccggct tccactcccc acataggaat 3771 agtccatccc cagattcgcc attgttcacc cctcgccctg ccctcctttg ccttccaccc 3831 ccaccatcca ggtggagacc ctgagaagga ccctgggagc tctgggaatt tggagtgacc 3891 aaaggtgtgc cctgtacaca ggcgaggacc ctgcacctgg atgggggtcc ctgtgggtca 3951 aattgggggg aggtgctgtg ggagtaaaat actgaatata tgagtttttc agttttgaaa 4011 aaaa 4015 2 1132 PRT Homo sapiens 2 Met Pro Arg Ala Pro Arg Cys Arg Ala Val Arg Ser Leu Leu Arg Ser 1 5 10 15 His Tyr Arg Glu Val Leu Pro Leu Ala Thr Phe Val Arg Arg Leu Gly 20 25 30 Pro Gln Gly Trp Arg Leu Val Gln Arg Gly Asp Pro Ala Ala Phe Arg 35 40 45 Ala Leu Val Ala Gln Cys Leu Val Cys Val Pro Trp Asp Ala Arg Pro 50 55 60 Pro Pro Ala Ala Pro Ser Phe Arg Gln Val Ser Cys Leu Lys Glu Leu 65 70 75 80 Val Ala Arg Val Leu Gln Arg Leu Cys Glu Arg Gly Ala Lys Asn Val 85 90 95 Leu Ala Phe Gly Phe Ala Leu Leu Asp Gly Ala Arg Gly Gly Pro Pro 100 105 110 Glu Ala Phe Thr Thr Ser Val Arg Ser Tyr Leu Pro Asn Thr Val Thr 115 120 125 Asp Ala Leu Arg Gly Ser Gly Ala Trp Gly Leu Leu Leu Arg Arg Val 130 135 140 Gly Asp Asp Val Leu Val His Leu Leu Ala Arg Cys Ala Leu Phe Val 145 150 155 160 Leu Val Ala Pro Ser Cys Ala Tyr Gln Val Cys Gly Pro Pro Leu Tyr 165 170 175 Gln Leu Gly Ala Ala Thr Gln Ala Arg Pro Pro Pro His Ala Ser Gly 180 185 190 Pro Arg Arg Arg Leu Gly Cys Glu Arg Ala Trp Asn His Ser Val Arg 195 200 205 Glu Ala Gly Val Pro Leu Gly Leu Pro Ala Pro Gly Ala Arg Arg Arg 210 215 220 Gly Gly Ser Ala Ser Arg Ser Leu Pro Leu Pro Lys Arg Pro Arg Arg 225 230 235 240 Gly Ala Ala Pro Glu Pro Glu Arg Thr Pro Val Gly Gln Gly Ser Trp 245 250 255 Ala His Pro Gly Arg Thr Arg Gly Pro Ser Asp Arg Gly Phe Cys Val 260 265 270 Val Ser Pro Ala Arg Pro Ala Glu Glu Ala Thr Ser Leu Glu Gly Ala 275 280 285 Leu Ser Gly Thr Arg His Ser His Pro Ser Val Gly Arg Gln His His 290 295 300 Ala Gly Pro Pro Ser Thr Ser Arg Pro Pro Arg Pro Trp Asp Thr Pro 305 310 315 320 Cys Pro Pro Val Tyr Ala Glu Thr Lys His Phe Leu Tyr Ser Ser Gly 325 330 335 Asp Lys Glu Gln Leu Arg Pro Ser Phe Leu Leu Ser Ser Leu Arg Pro 340 345 350 Ser Leu Thr Gly Ala Arg Arg Leu Val Glu Thr Ile Phe Leu Gly Ser 355 360 365 Arg Pro Trp Met Pro Gly Thr Pro Arg Arg Leu Pro Arg Leu Pro Gln 370 375 380 Arg Tyr Trp Gln Met Arg Pro Leu Phe Leu Glu Leu Leu Gly Asn His 385 390 395 400 Ala Gln Cys Pro Tyr Gly Val Leu Leu Lys Thr His Cys Pro Leu Arg 405 410 415 Ala Ala Val Thr Pro Ala Ala Gly Val Cys Ala Arg Glu Lys Pro Gln 420 425 430 Gly Ser Val Ala Ala Pro Glu Glu Glu Asp Thr Asp Pro Arg Arg Leu 435 440 445 Val Gln Leu Leu Arg Gln His Ser Ser Pro Trp Gln Val Tyr Gly Phe 450 455 460 Val Arg Ala Cys Leu Arg Arg Leu Val Pro Pro Gly Leu Trp Gly Ser 465 470 475 480 Arg His Asn Glu Arg Arg Phe Leu Arg Asn Thr Lys Lys Phe Ile Ser 485 490 495 Leu Gly Lys His Ala Lys Leu Ser Leu Gln Glu Leu Thr Trp Lys Met 500 505 510 Ser Val Arg Asp Cys Ala Trp Leu Arg Arg Ser Pro Gly Val Gly Cys 515 520 525 Val Pro Ala Ala Glu His Arg Leu Arg Glu Glu Ile Leu Ala Lys Phe 530 535 540 Leu His Trp Leu Met Ser Val Tyr Val Val Glu Leu Leu Arg Ser Phe 545 550 555 560 Phe Tyr Val Thr Glu Thr Thr Phe Gln Lys Asn Arg Leu Phe Phe Tyr 565 570 575 Arg Lys Ser Val Trp Ser Lys Leu Gln Ser Ile Gly Ile Arg Gln His 580 585 590 Leu Lys Arg Val Gln Leu Arg Glu Leu Ser Glu Ala Glu Val Arg Gln 595 600 605 His Arg Glu Ala Arg Pro Ala Leu Leu Thr Ser Arg Leu Arg Phe Ile 610 615 620 Pro Lys Pro Asp Gly Leu Arg Pro Ile Val Asn Met Asp Tyr Val Val 625 630 635 640 Gly Ala Arg Thr Phe Arg Arg Glu Lys Arg Ala Glu Arg Leu Thr Ser 645 650 655 Arg Val Lys Ala Leu Phe Ser Val Leu Asn Tyr Glu Arg Ala Arg Arg 660 665 670 Pro Gly Leu Leu Gly Ala Ser Val Leu Gly Leu Asp Asp Ile His Arg 675 680 685 Ala Trp Arg Thr Phe Val Leu Arg Val Arg Ala Gln Asp Pro Pro Pro 690 695 700 Glu Leu Tyr Phe Val Lys Val Asp Val Thr Gly Ala Tyr Asp Thr Ile 705 710 715 720 Pro Gln Asp Arg Leu Thr Glu Val Ile Ala Ser Ile Ile Lys Pro Gln 725 730 735 Asn Thr Tyr Cys Val Arg Arg Tyr Ala Val Val Gln Lys Ala Ala His 740 745 750 Gly His Val Arg Lys Ala Phe Lys Ser His Val Ser Thr Leu Thr Asp 755 760 765 Leu Gln Pro Tyr Met Arg Gln Phe Val Ala His Leu Gln Glu Thr Ser 770 775 780 Pro Leu Arg Asp Ala Val Val Ile Glu Gln Ser Ser Ser Leu Asn Glu 785 790 795 800 Ala Ser Ser Gly Leu Phe Asp Val Phe Leu Arg Phe Met Cys His His 805 810 815 Ala Val Arg Ile Arg Gly Lys Ser Tyr Val Gln Cys Gln Gly Ile Pro 820 825 830 Gln Gly Ser Ile Leu Ser Thr Leu Leu Cys Ser Leu Cys Tyr Gly Asp 835 840 845 Met Glu Asn Lys Leu Phe Ala Gly Ile Arg Arg Asp Gly Leu Leu Leu 850 855 860 Arg Leu Val Asp Asp Phe Leu Leu Val Thr Pro His Leu Thr His Ala 865 870 875 880 Lys Thr Phe Leu Arg Thr Leu Val Arg Gly Val Pro Glu Tyr Gly Cys 885 890 895 Val Val Asn Leu Arg Lys Thr Val Val Asn Phe Pro Val Glu Asp Glu 900 905 910 Ala Leu Gly Gly Thr Ala Phe Val Gln Met Pro Ala His Gly Leu Phe 915 920 925 Pro Trp Cys Gly Leu Leu Leu Asp Thr Arg Thr Leu Glu Val Gln Ser 930 935 940 Asp Tyr Ser Ser Tyr Ala Arg Thr Ser Ile Arg Ala Ser Leu Thr Phe 945 950 955 960 Asn Arg Gly Phe Lys Ala Gly Arg Asn Met Arg Arg Lys Leu Phe Gly 965 970 975 Val Leu Arg Leu Lys Cys His Ser Leu Phe Leu Asp Leu Gln Val Asn 980 985 990 Ser Leu Gln Thr Val Cys Thr Asn Ile Tyr Lys Ile Leu Leu Leu Gln 995 1000 1005 Ala Tyr Arg Phe His Ala Cys Val Leu Gln Leu Pro Phe His Gln Gln 1010 1015 1020 Val Trp Lys Asn Pro Thr Phe Phe Leu Arg Val Ile Ser Asp Thr Ala 1025 1030 1035 1040 Ser Leu Cys Tyr Ser Ile Leu Lys Ala Lys Asn Ala Gly Met Ser Leu 1045 1050 1055 Gly Ala Lys Gly Ala Ala Gly Pro Leu Pro Ser Glu Ala Val Gln Trp 1060 1065 1070 Leu Cys His Gln Ala Phe Leu Leu Lys Leu Thr Arg His Arg Val Thr 1075 1080 1085 Tyr Val Pro Leu Leu Gly Ser Leu Arg Thr Ala Gln Thr Gln Leu Ser 1090 1095 1100 Arg Lys Leu Pro Gly Thr Thr Leu Thr Ala Leu Glu Ala Ala Ala Asn 1105 1110 1115 1120 Pro Ala Leu Pro Ser Asp Phe Lys Thr Ile Leu Asp 1125 1130 

What is claimed is:
 1. A composition comprising antigen-presenting cells containing a polypeptide that comprises at least 6 consecutive amino acids of telomerase reverse transcriptase (TRT; SEQ. ID NO:2), and a pharmaceutical carrier suitable for human administration; whereupon administration of the composition to a human subject induces an anti-TRT immunological response.
 2. The composition of claim 1, wherein the antigen-presenting cells are dendritic cells.
 3. The composition of claim 1, wherein the antigen-presenting cells have either been pulsed ex vivo with a polypeptide containing said consecutive amino acids, or modified ex vivo with a polynucleotide encoding said consecutive amino acids.
 4. The composition of claim 1, wherein the polypeptide comprises at least 8 consecutive amino acids of SEQ. ID NO:2.
 5. The composition of claim 1, further comprising a cytokine.
 6. The composition of claim 5, wherein the cytokine is GM-CSF or IL-2.
 7. The composition of claim 1, wherein the immunological response comprises both TRT-specific antibody and TRT-specific cytotoxic T cells.
 8. A method for preparing the composition of claim 1, comprising isolating mononuclear leukocytes from peripheral blood, optionally fractionating or differentiating the leukocytes, and then either: a) pulsing the leukocytes with a polypeptide containing said consecutive amino acids; or b) modifying the leukocytes with a polynucleotide encoding said consecutive amino acids.
 9. The method of claim 8, wherein the leukocytes are pulsed with a polypeptide containing 8-12 consecutive amino acids of SEQ. ID NO:2.
 10. The method of claim 8, wherein the leukocytes are modified with a polynucleotide encoding at last 12 consecutive amino acids of SEQ. ID NO:2.
 11. A method for eliciting an anti-TRT immunological response in a subject, comprising administering to the subject the composition of claim
 1. 12. The composition of claim 1, wherein the antigen-presenting cells contain a plurally of such polypeptides.
 13. A method for preparing cytotoxic T cells specific for telomerase reverse transcriptase (TRT), comprising combining T lymphocytes ex vivo with antigen-presenting cells containing a polypeptide that comprises at least 6 consecutive amino acids of telomerase reverse transcriptase (TRT; SEQ. ID NO:2), so as to cause T lymphocytes specific for TRT to proliferate.
 14. The method of claim 13, wherein the antigen-presenting cells are dendritic cells.
 15. The method of claim 13, wherein the antigen-presenting cells have been pulsed ex vivo with the polypeptide.
 16. The method of claim 13, wherein the antigen-presenting cells have been modified with a polynucleotide ex vivo so as to express the polypeptide.
 17. A cytotoxic T cell produced according to the method of claim
 13. 18. A method for providing a subject with T cell immunity against target cells bearing TRT antigenic peptides, comprising administering to the subject cytotoxic T cells according to claim
 17. 19. An isolated cytotoxic T cell specific for telomerase reverse transcriptase (TRT).
 20. The cytotoxic T cell of claim 19, which is a CD8+ Class-I restricted T cell.
 21. A pharmaceutical composition comprising a plurality of cytotoxic T cells according to claim 19 in a pharmaceutically acceptable carrier suitable for human administration.
 22. A method for providing a subject with T cell immunity against target cells bearing TRT antigenic peptides, comprising administering to the subject cytotoxic T cells according to claim
 19. 